seacap wave energy converter


Seacap is a “point absorber” system : a buoy absorbs the vertical motion of ocean waves. It floats around a column fixed to the seabed, captures  and transfers the kinetic energy of the waves to electric linear generators. The modular nature of the system emphasizes safety and reliability, maintenance and performance, as well as survivability in extreme weather.

A 1:20th scaled model of the device has been tested in a wave tank, at DGA Hydrodynamics (Rouen, France), confirming previous CFD yield calculations by independant hydrodynamic experts: in sea state conditions typical of the French Atlantic, the load factor  can further be enhanced by means of a proprietary “latching” system. The new generation equipment should improve the performance even further.

Beyond the usual electricity production towards a shore base sub-station, the platform allows the on-site conversion of this energy into “clean hydrogen«  for new emerging market applications, particularly in the mobile sector (ground and marine transportation).

seacap modules

Suction foundation
Utility deck
Field array

state of the art

The economic viability of a wave energy converter (WEC) depends largely on its power take-off system (PTO). Active control of the PTO is necessary in order to maximize power capture across the wide range of sea-states encountered offshore and, can also improve survivability. 

As developer of an innovative WEC design made of several proven modular components and, ultimately integrator of a complete marine energy WEC, Hydrocap has made its primary goal to design SEACAP around the most reliable and efficient components, contributing to  bring to market a new step change generation of PTO. The economics of the system are directly proportional to the efficiency of the conversion process and the type of generators used (see below).

After analysis of numerous options, available, or in development, the solution retained by Hydrocap team has been a new type of direct-drive linear azymutal switched-reluctance electric generator, whose second generation is currently developed within SEA-TITAN, a European H2020 funded project started earlier this year, in which Hydrocap is a collaborative partner, together with leading European actors of the electrical and marine energy sector.

The overall objective of SEA-TITAN aims at achieving high and continuous peak force densities, using  advanced control strategies, in order to significantly reduce the levelized cost of energy (LCOE) and also the capital expenditures (CAPEX), simultaneously increasing the float to wire efficiency (FtWE), defined as the  ratio between the mechanical wave energy absorbed by the system and, the electricity output of the Seacap WEC. 

schematic of the energy conversion

(ref. JCR Ocean energy status report 2014)